Toolholder



Aug. 14,1945. E.- T. PRINGLE, .JR`

TOOL HOLDER Filed May l, 1944 ZCZZPM INVENroR,

Patented Aug. 14, 19,45

UNITED sTATEsrATi-L OFFICE I This invention relates to a device forholding tools and more especially cutting tools such vas used on lathes,one of the objects being tofprovide a holder which permits minuteadjustment of the held tool toward or from the work and whichhas a`further means whereby the tool is held securely in place following theadjustment and Without danger of shifting as a result of the vibrationto which it is subjected in use.

A further object is to provide a structure of this character which issimple landfcompact in construction and which can be operated readilyfor the purpose of adjusting and gripping the tool.

It is a fact well known that in metal working, where minute cutting,etc. of the work is necessary, difficulty has been experienced ineffecting the proper adjustment of the tool and holding the tool in `itsadjusted position, this being particularly true where measurements inthousandths of an inch are required.

The present invention has for an object the provision of means wherebythe necessary minute adjustment can be effected, can be indicated, andcan be maintained.

With the foregoing and other objects in yview which will appear as thedescription proceeds, the invention consists of certain novel details ofconstruction and combinations of parts hereinafter more fully described`and pointed out in the claims, it, being understood that changes may bemade in the construction and arrangement of parts without departing fromthe spirit of the invention as claimed. i

In the accompanying drawing the preferred form of the invention has beenshown.

In said drawing:

Figure 1 is a central longitudinal section through 'the holder, a toolbeing shown in position therein.

Figure 2 is a top plan View thereof.

Figure 3 is an end elevation.

Figure 4 is a section on line 4-4, Figure 1, the adjusting block beingshown in elevation.

Referring to the figures by characters of reference, I designates thebody of the holder which can be in the form of a block of any suitablesize and shape whereby it can be mounted properly on the particularmetal-working machine `with which it is to be used.` This block isprovided with an angular opening 2 extending longitudinallytherethrough. The bottom of the opening is cut away for a portion of itslength but throughout the width of the opening to provide an elongatedrecess 3 the bottom 4 of which is inclined downwardly. toward the openfront end of the recess.` Fitted snugly within this recess is a `Wedge'the top surface of which is parallel with thezlongitudinal axis of theopening `2,

and within the back o r small end ofthe wedge` is a bore 6 the wall ofwhich isscrew-threaded so that it can be engaged by an adjusting screwl. This screw :has an velongated smooth stem 8 mounted for rotation inabore il` extending from thesmallendof the recess' 3 to the back` end-oftheibody I andyiahead III constitutes the-:outer or exposed end of theshank or stem 8. An annular groove II is provided in the stem-8 andprojecting thereinto is a retaining screw I2 or the like the head vofwhich is locatedat one side of the body where it can be reached readilyfor feedingthe screw into or out of the groove, thereby to hold the stem8 against longitudinal movement i A longitudinal slot I3 is provided inthe top of the body I and opens downwardly into the opening 2. Anadjusting screw I4 is extended longitudinally of the slot and has areduced end portion I5 journalled in one wall of the slot while A nindex or pointer 2l is extended from the head I'I and cooperates with anannular series of graduations 22 on the adjacent surface of the body I.These graduations can be suitably designated and inpractice eachgraduation can represent an adjustment of a very small unit of measure isuch as a thousandths of an inch.

An adjusting block 23 is located` in the slot I3 and is mounted on thescrew I4. This block has ,a tongue- 24 extended therefrom into theopening 2.

The cutting tool has been indicated at 25 and can have its active end ofany suitable design, capable of doing the work required. The width ofthis tool is such as to insure a working fit against the sides of theopening 2 and the top and bottom surfaces of the tool are parallel. A

notch or recess 26 is provided in the top of the tool and isproportioned to receive and be snugly engaged by the tongue 24.

In practice the Wedge 5 is fed outwardly by turning the screw 'I in onedirection. Thus its top surface is brought below the level of the bottomwall of opening 2. The block 23 is inserted into the slot I3 so that itstongue 24 will drop into the recess 26 in the tool and thereafter screwI4 is inserted longitudinally into its bearings and becomes properlyseated therein after being fed through the block 23. When the screw hasbeen brought to its proper position, the retaining screw I9A is directedinto,` the groove I8 and there'aftenby rotating screw I4, the tool 25can be fed in either direction. The wedge 5 is adjusted inwardly so asto lightly engage the tool. 'I'he too1 is then adjusted minutely so asto make a cut of the desired depth after which the wedge 5 is adjustedinwardly asu'icient distance to clamp the tool tightly in place, therebyinsuring against accidental shiftiiglof` the-tool following its minuteadjustment. giving a slight turn to the screw l, the 'wedge can becomeslightly released from theltool and by then giving a desired turn to thehead. I'I `to insure a cut of the proper depth as indicated bythecooperating" elements 2| 'and' 22, the tool can `again be gripped"byadjusting the wedge as alreadyexplained. Y f

Whatfis claimed is: 1. A Itool 'holderincluding a body "having anopening extending thereinto and: a slot communicatingwith'the opening,an adjusting screw mounted for rotation in' saidbody'and extendinglongitudinally of the slot, means for holding said screw againstlongitudinal displacement, a member mounted on and shiftable b-y thescrew and slidable longitudinally of the slot, said member projectinginto the opening, cooperating means on the screw and body for indicatingthe extent of movement of the member by the screw, and a too1 slidablymounted in the opening and having a notch into which said member isextended'.

2. .The combination with atool having a recess extending thereinto, of aholder for the tool including a body having an opening into which thetool is extended, there being a longitudinal slot in the bodycommunicating with said opening Iand a recess in the body opposite tothe slot,

screws extending across the slot and longitudi- 'nally thereof `and intothe recess respectively,

meansY for holding the respective screws against longitudinal movement,said screws being mounted for rotation,'a block in the slot and on oneof=the screws, said block having an integral portion extended into'therecess inthe tool, a wedge .within the recess and bearing on theinclined surface'thereof, said wedge having a surface parallel with' thelongitudinal axis of the opening, Asaid wedge being in engagement withand `adapted to be adjusted by thel other screw thereby to clamp uponthe too1 Within the opening.

` EDWARD THOMPSON PRINGLE,'JR.

